Coring apparatus



Sept 21, 1943- J. c. STOKES 2,330,155

GORING APPARATUS Filed May 11, 1942 2 Sheets-Sheet 2 I1 x1! 45 'L' y d 7 1 3Q 4l .38 36 '4o J/s//v C( J70/f5.1

' INVENTOR.

Patented Sept. 21, 1943 CORING APPARATUS John C. Stokes, Houston, Tex., assignor to Reed Roller Bit Company, HonstonrTex., a corporation oi Texas Application May 1l, 1942, Serial No. 442,398`

7 Claims.

This invention relates to coring apparatus and has for its general object the provision of an improved full floating barrel type of core drilling apparatus.

The invention relates particularly to that type of coring apparatus which is ordinarily referred i to as a conventional coring apparatus. That is, it is to that type of coring apparatus in which there is a core drill carried on a lower end of a drill stem and an inner core barrel mounted within such core drill and within the lower end of the drill stem to receive a core, but which is not movable upwardly through the drill stem.

In this type of coring apparatus it is highly desirable that the core barrel which is within the core drill and which is adapted to receive the core be so mounted that it is freely rotatable and capable of taking both upward and down-Y ward thrusts. s

It is therefore an object of this invention to provide such a coring apparatus and toprovide a suspension for the core barrel which will allow it to rotate and float freely during the taking oi' a core.

Another object of this invention is to provide a means whereby such inner core barrel assembly may be suspended to take both upward and downward thrust and to permit free rotation of the inner core barrel, but which will be quickly and easily releasable so as to permitl the entire coring assembly to be removed from the lower end of the drill stem after the core bit has been iirst removed.

Other objects and advantages of this invention will become apparent from the following description taken in connection with the accompanyingl drawings wherein is set-forth by way of illustration and example one embodiment of this invention.

In the drawings:

Fig. 1 represents a longitudinal cross section through the upper portion of a coring apparatus constructed lin accordance with this invention and illustrating the means for suspending the inner core barrel assembly, such means in this instance being shown in such position as to suspend the core barrel.

Fig. 2 is a view similar to Fig. 1 but illustrating the lower portion of the same apparatus.

Fig. 3 is a transverse cross section taken along the line 3-3 of Fig. 1.

Fig. 4 is a transverse cross section taken along the line 4-4 of Fig. l.

Fig. 5 is a view similar to Fig. 1 but showing the parts in the position they occupy when the in barrel vassembly has been released for re Noval from the coring apparatus.

g, 6 is a view on a reducedscale illustrating th apparatus shown in Figs. .1 to 5 inclusiveV p rtly in side elevation and partlyin vertical cross section.

Referring now more particularly to the drawings, the numeral I designatesy a conventional outer core barrel with a so-called coring head or core bit 2 secured to the lower end thereof. It is n'oted that the connection between the outer core barrel I and the coring head 2 is provided by means of a sub 3 which may be designated the lower sub. This sub is preferably welded at 4 to the lower end of the outer core barrel so as to provide -a permanent connection with said core barrel.

At its upper end the outer core -barrel I is threaded at 5 and welded at B to a suspension iitting 'I which has a coarse external thread 8 on its upper end portion and whichextends beyond this coarse upperthread in the form of a sleeve 9 having radial openings IB therethrough spaced circumferentially from each other and adapted to receive balls II. It will be noted that the openings I0 and the balls II are of such diameter that when the ballsk are caused to lie tangent to one surface of the sleeve 9 they will project beyond the opposite surface. That'is, the balls are of greater diameter than thel thickness of the wall of the sleeve 9. Also, the sleeve 9 adjacent its upper end is provided with a. circumferential groove adapted to receive a spring ring i2 which projects radially outwardly from the outer sur- -face of this sleeve for a purpose presently to be described.

The coring head 2 may be of any form which is found desirable for the formation in which the drilling is to take place, but there is illus- ,i

trated in the drawings a form of coring head which is adaptedfor use in hard formations. Such coring head is provided with cuter cutters I3 and inner cutters I4. These are adapted to cut an annular path and to leave a core I5 which as the drilling continues moves past the coreV catchers I6 within the coring head and upwardly through the fitting I1 on the lower end of the inner core barrel I8 and into the inner core barrel itself.

At its upperend, the inner core barrel is vpro-" 'adaptedto receive a bearing bar 23. Above this bearing head 22 the bearing bar is provided with a downwardly facing shoulder 24 which is opposed by a countersunk portion providing an upwardly facing shoulder 25 in the upper end of the bearing head 22. Between these two shoulders there is interposed a series of bearing rings of any suitable material such as rubber or a rubber substitute. Such rings are designated at 26.

Similarly, this bearing bar is held in place within the bearing head 22 by means of a nut 21 threaded on to its lower end and providing an upwardly facing shoulder 28 which opposes a downwardly facing shoulder29 formed at the upper end of a countersink in the lower end of the bearing head 22. Between these two shoulders there is likewise placed a suitable thrust ring providing a thrust bearing for preventing downward movement of the bearing head 22 with respect to the bearing bar 23. This last mentioned bearing ring is designated 30.

For the purpose of preventing the nut 21 from backing off during use and thus dropping the inner core barrel, the bearing bar 23 is provided with circumferential grooves adapted to receive a spring ring 3i Just below the nut 21 when it is fully tightened in place. The bearing bar 23 is also hollow and is internally threaded at its lower end for the purpose of receiving a hollow plug 32 which in turn holds a valve seat element 33 in place. This valve seat element 33 is adapted to receive a ball valve 34 which serves as a downwardly closing check valve to .permit uid to be forced out of the upper end of the inner core barrel during the taking of a core but to prevent fluid from flowing downwardly from the upper end into the inner core barrel.

Intermediate its ends this tting 42 is provided with a restriction which is of a diameter only slightly larger than the external diameter of the sleeve 8. The upper end of this restricted portion provides a relatively sharp or abrupt upwardly facing shoulder 46 while the lowerend is tapered outwardly to the full inner diameter of the fitting 42 as shown at 41. It will be seen that when the parts are in the position illustrated in Fig. 1 with the threads' and 43 fully engaged with each other the balls Il will be held inwardly by the restricted portion just below the shoulder 46. 'When these balls are thus held inwardly they engage the groove 4I in the bearing bar 23 and serve to support this bearing bar against either upward or downward thrust. The bearing bar in turn provides a thrust bearing for supporting against thrust ineither direction the bearing head 22 from which the inner barrel is suspended. The inner barrel is thus provided with a full fioatingsupport so that it may rotate freely and at the same time be supported against upward or downward movement.

When it is desired to remove the inner core barrel assembly, the coring head 2 is first unscrewed and removed. Then the connection be- Intermediate its ends the bearing head 22 is provided with a groove adapted to receive a U- shaped packing ring 35 that forms a seal about the bearing bar and prevents the downward flow of fluid through the bearing head 22 around the outside of the bearing bar.

Above the bearing head 22 the bearing bar is provided with lateral openings 36 through which any upward flow past the ball valve 34 may escape into the outer core barrel. Also above these openings 36 there are other downwardly and outwardly directed lateral openings 31 through which slush that is pumped downwardly through the drill stem may escape into the space between the inner and outer barrels. openings 36 and 31 there is disposed a slush plug 38 that is held in position by means of a cotter key 39. This slush plug has a downwardly extending part of reduced diameter shown -at 4U which serves to prevent the ball valve 34 from being forced upwardly and out of the upper end of the bearing bar 23.

This bearing bar 23 is adapted to extend upwardly into the passageway through the fitting 1 so that its upper end projects slightly past the openings l0. On its outer surface it is formed with a circumferential groove 4l which is adapted to receive the balls Ii when they are moved radially inwardly.

For the purpose of holding the balls il in- In between the wardly into engagement with the groove 4i, a

fitting 42 is provided at its lower end with coarse threads 43 adapted to engage the threads 8 on the fitting 1. 'I'he upper end of this tting 42 is provided with internal threads 44 to engage the external threads on the pin 45 on the lower end of the drill stem.

tween the threads 8 and 43 is loosened so that the fitting 1 is allowed to move downwardly with respect to the fitting 42. When this occurs the balls I i move out of the restricted portion of the fitting 42 and downwardly along the tapered portion 41 to a part of larger diameter within the fitting 42. This permits them to move radiallyv outwardly and disengage themselves from the circumferential groove 4i in the bearing bar 23. With the balls thus disengaged the bearing bar is free to move downwardly with respect to the fitting 1 and inasmuch as there is no other connection holding it within the assembly it may be removed bodily. Thereupon the core which has been taken may be taken out and the entire assembly replaced for further coring operation. When the assembly has been replaced the threads 8 and 43 will again be engaged with each other and as this engagement is tightened the balls Il will be moved upwardly along the tapered portion 41 within the fitting 42 and as this movement occurs they will be forced inwardly into the groove 4i in the bearing bar 23.

From the foregoing it will be seen that a means has been provided for a coring apparatus which makes possible a full floating suspension of an inner core barrel of the conventional type, but at the same time a suspension which may be quickly released whenever desired to permit the bodily removed of the entire inner core barrel assembly. It may be mentioned that when the threads lil and 43 are released or partially released from each other, the extent of such release 1s limited by the position of the spring ring i2 which comes into engagement with the shoulder 4.6 within the fitting 42 so as to prevent the fitting 1 from dropping out of the fitting 42. This prevents the operator from inadvertently unscrewing these two ttings from each other to too great an extent so as to drop the outer core barrel assembly. Spring i2 may be removed from its slot when desired by the insertion of a screw driver or similar tool into one or more of the slots 41.

It will, of course. be appreciated that the plug 38 may, 1f and when desired,- be removed and that the apparatus may be utilized without this plug 1f such operation is found more desirable. With the plug removed, the ball 34 may be left zii/*Aussie Ccrr said members when the same are moved radially inwardly to lock said parts together, and relatively movable means on said outer bearing part to force said latching members radially inwardly to engage with said circumferential groove.

2. In a coring apparatus, an outer barrel, an inner barrel, a bearing bar projecting upwardly from the upper end of said inner barrel, a suspension sleeve carried by said outer barrel in a position opposite said bearing bar, said sleeve having radial apertures therein, a ball in each of said apertures said balls having diameters greater than the thickness of the wall of the suspension sleeve, and said bearing bar having a circumferential groove therein adapted to receive said balls when moved radially inwardly to lock said inner and outer barrels together, and relatively movable means on said outer barrel to cause radially inward movement of said balls to engage said circumferential groove.

3. In a coring apparatus, an outer barrel, an inner barrel, a bearing bar projecting upwardly from the upper end of said inner barrel, a suspension sleeve carried by said outerbarrel and disposed about and opposite said bearing bar, said sleeve having a plurality of radial apertures therein, a ball in each of said apertures of a diameter greater than the thickness of the wall of said sleeve, said bearing bar having a circumferential groove therein adapted to receive said balls when the same are moved radially inwardly, means telescopingly engaging over said suspension sleeve and having a part of smaller diameter adapted to engage said balls and force them radially inwardly into engagement with said circumferential groove, and a part of relatively larger diameter adapted to permit said balls to move radially voutwardly to disengage the same from said circumferential groove.

4. In a coring apparatus, an outer barrel, an

inner barrel, a bearing bar projecting upwardly `from the upper end of said inner barrel, a suspension sleeve on said outer barrel surrounding and substantially opposed to said bearing bar onA the inner barrel, said sleeve having a plurality of radial openings therein, a plurality of balls one in each of said openings, said balls being of a diameter greater than the thickness of the walls of said sleeve, said bearing bar having a circumferential groove therein adapted to receive said balls when the same are moved radially inwardly to lock said inner and outer barrels together, a member telescopingly engaging over said suspension sleeve and having a part of smaller internal diameter adapted to engage and force said balls radially inwardly into engagement with said circumferential groove and a part of relatively sov operating threaded parts adapted to be engaged with each other to hold said member in position such that said balls will be held radially inwardly.

5. In a coring apparatus, an outer barrel, an inner barrel, a bearing bar on and extending from the upper end oi said inner barrel, a suspension sleeve within said outer barrel surrounding and opposed to said bearing bar, said sleeve having a plurality of radial openings therein, a plurality of balls one in each of said openings, said balls being of a diameter greater than the thickness of the walls of said sleeve, said bearing bar hav. ing a circumferential groove therein adapted to receive said balls when the same arel forced radially inwardly to lock said inner and outer barrels together, a member telescopingly engaging over said suspension sleeve and having a part of relatively smaller internal diameter adapted to engage and force said balls inwardly into engagement with said circumferential groove and a part of relatively larger internal diameter adapted to permit said balls to move radially outwardly and disengage from said circumferential groove, threads on said member and said suspension sleeve for holding said member in position to urge said balls radially inwardly, and a pair of stops on said member and said suspension sleeve for limiting the disengagement of said threaded parts from each other whereby said parts will be prevented from being accidentally separated.

6. In a coring apparatus, an outer barrel, anV inner barrel, a bearing part in said outer barrel, a bearing bar projecting upwardly from the upper end of said inner barrel and located substantially opposite the bearing part in said outer barrel, radially movable latching members mounted in the bearing part in said outer member, said bearing bar opposite said membersl having a depression therein adapted to receive said members when the same are moved radially inwardly to lock .said parts together, and relatively movable means on' said outer bearing part to force said latching members inwardly to engage with said depression.,

7. In a coring apparatus, an outer barrel, an i telescopingly `engaged over said bearing parts and having a part of relatively smaller internal diameter adapted to engage and force said latching members inwardlyinto engagement with said depression and a part of relatively larger internal diameter adapted to permit said latching members to move radially outwardly and disengage` from said depression, threads on said telescoping member and said outer barrel for holding l'said telescoping member in position to urge' said latching members radially inwardly, and a pair of stops on said telescoping member and on the larger internal diameter adapted to free said bearing part on sad outer barrel for limiting the disengagement of said threaded parts from each other whereby said parts will be prevented from l being accidentally separated.

JoHN c. erom. 

